As Britain's most pro-European politician, Nick Clegg probably never thought he would turn to South Africa for inspiration. But the deputy prime minister has entrusted Ryan Coetzee, one of the key figures behind the success of South Africa's Democratic Alliance party, with the vital pre-election role of Liberal Democrat strategy director.

Coetzee, 39, is taking over from Richard Reeves, the biographer of JS Mill and former Observer journalist, who has moved to the US. Where Reeves was grand on political theory Coetzee will have a relentless and practical focus on delivering – and then promoting – tangible changes through government policy.

Coetzee is well known to Jonny Oates, Clegg's chief of staff, who used to live in South Africa. But Coetzee came to the party's attention when he stopped off in London in June en route from South Africa to the US as a member of a delegation of African Liberal leaders.

Coetzee told senior Lib Dem figures how the Democratic Alliance, which is now South Africa's main opposition party, went from 1.73% of the vote in the first post-apartheid elections in 1994 to 16.66% in 2009. The Lib Dems were particularly struck with Coetzee's description of how his party won the elections in the Western Cape – the only province run by a non-ANC party – in 2009. After the party's victory Coetzee became a special adviser to Helen Zille, the party leader, who is premier of the Western Cape.

Coetzee told the meeting that Zille slowly built up a reputation for successful delivery of change when she replaced the ANC's Nomaindia Mfeketo as mayor of Cape Town in 2006. Zille's success there helped her displace the ANC's Lynne Brown as premier of the Western Cape in 2009.

One Lib Dem source said: "Ryan made quite an impression on our key people. He talked about how the party managed to get a foothold when it won the mayoralty in Cape Town. It used that to show it could deliver. His key message was that you have to develop a strategy that is appropriate to delivery in government. You have to be really clear and show how the things you are doing in government tie in together in terms of a coherent whole and project them as a coherent message."

Clegg and Oates missed Coetzee in June because they were at the Rio +20 summit. But the deputy prime minister and his chief of staff met Coetzee when he passed back through London on his way home from the US. Oates had given a nod of approval when he was asked about Coetzee by the Lib Dems who had seen him in June.

Some members of the Democratic Alliance are said to be slightly surprised by Coetzee's move. "There is bemusement," according to one source familiar with the thinking of some senior figures in the party. Zille was said to be "not overjoyed" at the appointment, according to South Africa's Independent Online.